Conventionally, systems and methods of conveying a sheet between a plurality of apparatuses are known. In such sheet conveyance systems, generally, sheet conveyance is controlled while executing data communication between the apparatuses.
A sheet conveyance system has recently been proposed, which connects a plurality of apparatuses over a network and causes each apparatus to directly transmit/receive commands to/from a plurality of apparatuses regardless of whether the apparatus is an adjacent apparatus (Japanese Patent Laid-Open No. 9-222961). A network sheet conveyance system of this type is superior to a conventional one-to-one connection system because a communication delay need not be taken into consideration.
More specifically, the network sheet conveyance system includes a plurality of apparatuses to execute communication by using a plurality of communication channels each of which is set in one of the transmission mode and a reception mode. A sheet is conveyed between the plurality of apparatuses.
However, the network sheet conveyance system has no sufficient measures against reception overflow that is caused due to transmission concentration from the apparatuses to a specific one. For transmission data of some types, the speed of command response is too low.